Reversible vane pump



P 1955 A. J. JANIK 2,716,947

- REVERSIBLE VANE PUMP Filed May 12, 1950 2 Sheets-Sheet l INVENTOR. ,4/vr0/v 1 JAN/K P 6, 1955 A. J. JANIK REVERSIBLE VANE PUMP 2 Sheets-Sheet 2 Filed May 12, 1950 Em W n m N m m T a N a A 5 M United States Patent f) REVERSIBLE VANE PUMP Anton J. Janik, Elyria, Ohio, assignor to The Ridge Tool Company, Elyria, Ohio Application May 12, 1950, Serial No. 161,660 3 Claims. (Cl. 103138) This invention relates to pumps and more particularly to a reversible rotary pump having improved vanes.

A great many different rotary pumps have been built in the past. Each was an attemptto overcome some particular problem and in so doing raised new problems. One of the simplest of the many proposed types of rotary pumps is the vane pump having an eccentric rotor in a chamber and carrying vanes which wipe the walls and pump the fluid by reason of the decreasing volume as the vanes approach the point where the eccentric mounted rotor most nearly touches the chamber wall.

Serious diliiculties have been experienced with this type of pump by reason of the eccentricity. Spring loaded vanes adapted to slide into and out of the rotor have been used in order to maintain contact between the wall and vane throughout the entire cycle. However, under repeated flexings at moderate to high speeds, springs weaken or break. Continuous vanes have also been used extending through both sides of the rotor and slidably disposed therein. However, with this type of vane, the chamber wall must be formed with a curve either mathematically derived or mechanically laid out to accommodate a rigid blade. This formation increases the cost of the housing because of the added machining processes required to finish the inner surface of the chamber. Blades of this type have also been provided with springs to permit the use of circular chamber walls, but again these have not been successful because of the weakness of the spring.

Still another disadvantage of the rotary type of pump is the necessity of turning the shaft in only one direction. Thus, each pump required two models, a left hand and right hand rotating model to be adapted to all. installations. Attempts to overcome this disadvantage included pumps which pumped in one direction when rotated one way and reversed the flow when turned the other way. This required careful handling of the connections to the pump in order to be sure the flow wouldbe in the proper direction through the pipes. Another device used included a movable chamber arranged so that the chamber could be turned in the housing to change the relative positions of the inlet and outlet ports with respect tothe rotor and the tubing or pipe connections for inlet and outlet.

By my invention, I provide an improved type rotary pump which may be rotated in either direction without manual change of any parts and still cause the fluid to flow through the same inlet and outlet ducts. The pump chamber has a circular wall, and no springs are used in the rotor at all. These advantages are accomplished by a system of poppet valves and manifolding which is not complex yet which fully serves the required purpose. The vanes in the rotor are formed from a resilient material, such as rubber or a synthetic rubber material which is resilient enough to be displaced the amount required to keep a tight seal between the vanes and a circular chamher.

A more complete understanding of the invention may be had from reference to the following figuresand description which form a part of this specification.

In the drawings:

Fig. l is an end elevational view of my pump from the shaft end;

Fig. 2 is an exploded view of the pump from the side;

Fig. 3 is anclevational view of the housing with the cap and valve plate remo'vcdi i l i Fig. 4 is a medial sectional view from line 44 of ig3; Fig. 5 is a plan view of one rubber vane;

Fig. '6 is a plan view of another rubber vane;

Fig. 7 is a view of the valve plate alone; and

Fig. 8 is a view looking into thecap.

Briefly, my invention comprises a rotary vane pump I having a circular cylindrical pump chamber in which an e'ccentrically mounted rotor" carries vanes made of a resilienfima'terial which can be displaced sufliciently to engage the walls of the chamber at all times. A series of chambers and a system of valves is provided, arranged so that the flow of the fluid will always be from one tubing pipe or inlet connection to its opposite outlet connection.

More specifically, and referring to the drawings, throughout which like numbers refer to like parts, the pumpis enclosed agenerally circular body or housing 'This' body may be cast integrally with the mounting feet 12 and the bearing housing 13. As can be best seen in Fig. 1, the bearing housing'an d body are not concentrio with each other but are slightly eccentric. The housing is formed with bosses 15511 diametrically opposite sides in: which thradedholes 1 4 and 14' are formed for the connec'tion'of the necessary tubing or conduits to carry the fluid to be pumped. A cap 16 is fastened to the housing by screws 1'7 to enclose it and to provide'manifoldingchambers as will appear later. A plate 18f which serves as avalve plate is interposed. between the housing 11 and the cap 16 and is' held in place by the cap 16 and i r s The inside of the housing 11 is formed into a plurality of chambers. The center chamber 2llis a circular cylindr ical chamber in which is disposeda rotor 21, eccentrir cally disposed in relation to the chamber. The rotor 21 is carried on a shaft 22 which is journalled in a bronze bearing 23 in the bearing housing'13,this shaft extend ing into the chamber eccentric to the chamber; in this instance, the eccentricity being approximately inch on the radius although obviously the amount of eccentricity wouldv ary. At its other end, the shaft may be provided with a gear 24, or the like, to provide driving means for the rotor. An oil seal 25 maybe provided about the shaft i dqSired- The rotor 21 is of circularformation and has two diametrical slots in which are disposed vanes 27 formed of a resilient material similar to rubber. Since one of the anticipated uses of the pump is as an oil pump, the preferredmaterial is one of the oil resistant synthetic rubbers, but it will be recognized that any soft resilient rubberlike material. may be used. These vanes are made largeenough to extend across the full diameter of the pump-chamber 2 9. As they turn with the rotor 21, they are carried through a path where the distance between ends of' a straight'line is somewhat less than the diameter. However, since the vanes are made of the rubber-like material, they simply displace longitudinally and are in "contact with the surface at all times." Moreover, the vanes are made wide enough to engage the surface of the pump chamber 20 along the sides 'of the vanes, thus assuring a truly positive dis placement pumpof excellent volumetric efficiency. The

vanes), Fig. 3, due to the] rotor 21 being eccentrically.

ii i te ia e are the 10, aresfidabk h s the diametrical lot a 5 ex en ou wa i em t e Pa:

riphery of the motor a distance less than the thickness of said vanes.

In order to use the two vanes 27, both extending completely across the chamber 20, it is necessary to interlock the vanes by some method. The preferred forms are shown in Figs. and 6. One vane 27a is formed with a rectangular opening 28 in the center approximately the size and shape of a transverse cross section of the blade but certainly long enough to allow the vane to slide the requisite distance in its slot. The other vane 27b is formed with a necked down section. The neck 29 is approximately square so that it slides freely in the opening 28. To assemble the two vanes, the necked vane 27b is inserted into the opening 28 until it can be turned. It is then turned 90 degrees and arranged so that the vanes are properly disposed to be inserted into the rotor slots. It is apparent that by this construction, each vane is enabled to slide relative to the other in its slot; and at the same time, there will be a minimum tendency to buckle over upon being compressed. The vane 27:: is not likely to bend because of the support remaining at the two edges 30. Nor is the vane 27b apt to bend, since its remaining support is at the center of the vane so that a uniform compression load on the end of the vane will simply displace the neck portion 29.

it will be apparent to those skilled in the art that the crossed vanes of the rotor could be formed in a single piece. However, in such a device, since the vanes are not relatively slidable, each portion of the vane must extend as far from the center of the rotor as the right hand part of the horizontal vane of Fig. 3. As that vane moved around, the material of the vane would be displaced inwardly into the central opening 31, which would have to be sufficiently large to accommodate the displaced material. This type of device thus requires more shortening of the vanes by such displacement, and, therefore, is considered less desirable, than the preferred arrangement previously described.

It will also be apparent to those skilled in the art that a pump of this type will operate with more or fewer vanes. A single two-ended vane, for instance, works very satisfactorily. Such a vane may either be a complete piece of solid material or may he cut out like either of the vanes 2701 or 27b. These latter are somewhat more compressible at their center portions and, therefore, may be preferred even in a single vaned pump.

Inlet and outlet ports 32 are provided into the pump chamber 20. These ports are symmetrically spaced about a line between the centers of the rotor and the pump chamber (a horizontal line in Fig. 4). Thus it is apparent that either one could be an inlet or outlet port dependent on the direction of rotation of the rotor.

As is customary in the art, relieved areas 33 are provided on each side of the ports to provide for more eflicient fluid flow into and out of the pump.

Each of the ports 32 connects the pump chamber with a valve chamber 34 formed in the pump housing 11. These chambers 34 are covered by the valve plate 18 which is provided with orifices 35 controlled by spring loaded poppet valves to assure the proper direction of fluid flow regardless of the direction of rotation of the rotor.

An inlet valve 36 is provided in each valve chamber 34. These valves are of identical construction and com prise a valve member 37 having a flat face 38 and a guide portion 39 protruding therefrom and adapted to extend through an orifice 35. A washer 40 of rubber or similar material is provided at the valve face 38 to assure a good seal and a spring 42 surrounds the stem 43 and seats against a shoulder. The other end of the spring seats in a hole 45 drilled in the wall of the valve chamber 34 opposite the plate 18. Thus, the valve will admit fluid freely into the chamber 34 but seals tightly against any discharging fluid.

It will be noted (Fig. 3) that both holes 45, and therefore both inlet valves 35, are on one side of a vertical centerline. The orifices 35 controlled by these valves communicate with a common inlet manifolding chamber 46 formed in the cap 16. The fluid enters this inlet chamber 46 through an orifice 47 leading from the inlet 14 in the housing. An outlet chamber 48 is also formed in the cap 16. Two outlet valves 49 substantially identical to the inlet valves 36 are provided in this chamber 48 having their springs 42 seated in holes 50 in the wall of the chamber. These valves 49 control a pair of orifices 35, each of which leads to a different valve chamber 34. Thus, each valve chamber 34 is isolated from the fluid flow by an inlet valve 36 and an outlet valve 49. Each valve chamber 34 is therefore adapted to act as either an inlet or an outlet chamber to the pump chamber 20. The outlet chamber 48 connects to the outlet 14' by an open orifice 52 similar to the inlet orifice 47. It will be apparent that the inlet 14 and outlet 14' could lead directly into the inlet chamber 46 and outlet chamber 48 in the cap 16 instead of into the housing 11 as illustrated. The illustrated embodiment is preferred, however, since the permanent tubing or pipe connections are made to the housing 11 which is fixed in place, and the cap 16 can be easily removed for inspection or the like.

The flow of fluid through the pump is controlled by the valves and depends on the direction of rotation of the rotor. If the rotation of the rotor were clockwise in Fig. 3, the fluid would be drawn in through the upper port 32. This would cause a slight vacuum in the upper valve chamber 34 and cause the inlet valve 36 in that chamber to open and the outlet valve to seal closed. Fluid would then enter that upper chamber from the inlet chamber 46 in the cap 16 through the orifice controlled by the open valve. This fluid would be carried around by the vanes 27 and discharged through the lower port 32 (Fig. 3) entering the lower valve chamber 34. The increase in pressure in this chamber would press the inlet valve 36 in this lower chamber tight shut, and at the same time would open the outlet valve 49 to allow the fluid to discharge through the outlet chamber 48 and the outlet 14.

If the direction of rotation of the rotor were reversed, it is apparent that the operation of the valves would automatically be reversed and that the flow would then be from the inlet 14 to the inlet chamber 46, then through the lower inlet valve 36 into the lower valve chamber 34, through the pump chamber 20 and out the upper valve chamber 34, its outlet valve 49 and the outlet chamber 48.

Thus, I have provided an inexpensive form of pump having an eccentric circulator rotor in a circular cylindrical chamber and one which is capable of being rotated in either direction without altering the flow direction of fluid into or out of the pump.

Having thus described my invention, I am aware that numerous and extensive departures may be made therefrom without departing from the spirit or scope of my invention.

Iclaim:

1. A rotary pump comprising a housing and a cylindrical pump chamber formed therein, a rotor rotatably disposed eccentrically in said chamber, a cylindrical chamber formed centrally in said rotor and a pair of elongated diametrical slots formed in said rotor and opening into said cylindrical chamber in said rotor and dividing said rotor into four equal segments, a pair of soft resilient vanes slidably disposed in said slots, each of said vanes having diametrically opposite surfaces in sliding engagement with the walls of said pump chamber, one of said vanes being formed with an opening through its broad side at the center thereof, and the other of said vanes having a necked down portion at its center, said necked down portion of said vane member being positioned within said center opening of said first mentioned 5 vane member and extending across substantially the entire width thereof, the side surfaces of said necked down portion being in slidable relaticnship to the edges of said central opening in said first mentioned vane member, and thereby providing support for said vane members within the cylindrical chamber of said rotor, the sides of said vane members being in slidable engagement with the sides of said segments and providing support therefor, said vane members having a portion extending outward from said rotor a distance less than the thickness of said vanes, and arranged to engage the walls of the cylindrical pump chamber.

2. A rotary pump comprising a housing enclosing a cylindrical pump chamber, a rotor rotatably disposed eccentrically in said chamber, said rotor being formed with diametrical slots and a central opening at the juncture of said slots, vanes disposed in said slots formed of a displaceable soft rubber-like material, a portion of each of said vanes extending outward from said rotor, and engaging the walls of said chamber, said vanes being slidable in said slots whereby the length of said extending portions is variable up to a value slightly less than the thickness of said vane material, said vanes being displaced in said central opening as the rotor surface adjacent said vanes approaches the wall of said chamber during its rotation.

3. A rotary pump comprising a housing enclosing a cylindrical pump chamber, a rotor rotatably disposed eccentricaly in said chamber, said rotor being formed with a pair of diametrical slots, a pair of soft resilient vanes slidably disposed in said slots, one of said vanes 6 being formed with an opening through its broad side at the center, the other of said vanes having a necked down portion at its center extending through said opening, said" vanes thereby being slidable relative to each other, and having a portion extending outward from said rotor a distance less than the thickness of said vanes and arranged to engage the walls of said pump chamber.

References Cited in the file' of this patent UNITED STATES PATENTS 161,909 Stenberg Apr. 13, 1875 199,737 Noteman Jan. 29, 1878 629,796 Lobee Aug. 1, 1899 786,466 Smith Apr. 4, 1905 861,626 Young July 30, 1907 999,753 Curtis Aug. 8, 1911 1,035,449 Kinney Aug. 13, 1912 1,053,321 Schrock Feb. 18, 1913 1,307,602 Schirmer June 24, 1919 2,052,474 Johnson Aug. 25, 1936 2,193,177 Laythorpe Mar. 12, 1940 2,258,371 Wernert Oct. 7, 1941 2,293,119 Davis Aug. 18, 1942 2,435,279 Hubacker Feb. 3, 1948 2,452,471 Jones Oct. 26, 1948 2,466,440 Kiekhaefer Apr. 5, 1949 2,520,087 Helmrich Aug. 22, 1950 2,580,278 Brennan Dec. 25, 1951 FOREIGN PATENTS 28,907 Great Britain of 1902 

